Emf (1 Viewer)

miss giggles

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Hi,
Can someone please explain to me the concept of emf and
is back emf the same as induced emf and what and how are induced currents produced
I'm really confused on this topic
 

nightweaver066

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EMF = Electromotive force.

It is synonymous with potential difference and voltage, the things that cause charged particles to move.

Back EMF is only the same as induced EMF when it opposes the supplied EMF.

In a motor, when the power source is switched on and the armature is constantly rotating, as it is a conductor experiencing a change in magnetic flux (constant rotation in the magnetic field), by Faraday's law, an EMF will be induced. This EMF induced will oppose the changing magnetic flux (Lenz's law), meaning it will oppose the supplied EMF.

When a conductor apart of a closed circuit moves in a magnetic field, i.e. experiences a change in magnetic flux, by Faraday's law, an EMF will be induced causing a current to flow in the circuit, the induced current.
 

nightweaver066

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Posted my response before i saw yours Spiral, didn't mean for you to delete your response. Was anticipating an awesome explanation.
 

SpiralFlex

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I mis-read question haha. Was about to do a 3 hour explanation...Oh my, Goodbye HSC. :(
 

iSplicer

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Excellent answers from both nightweaver066 and amycompton. Make sure you guys refer to Faraday's law and Lenz's law in your explanations, and include a diagram if possible in your answer.
 

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